Phase 1

lib3270j/src/main/java/haus/nightmare/lib3270j/Telnet3270Client.java

@@ -39,6 +39,8 @@ public class Telnet3270Client {
     private final DataStreamProcessor dsProcessor;
     private final TelnetFSM fsm;
     private final InputProcessor inputProcessor;
+    private final haus.nightmare.lib3270j.ecl.ECLPS ps;
+    private final haus.nightmare.lib3270j.ecl.ECLOIA oia;
     private TelnetConnection connection;
 
     public Telnet3270Client(ConnectionConfig config) {
@@ -49,6 +51,8 @@ public class Telnet3270Client {
         this.dsProcessor.getQueryReplyBuilder().setGraphicsMode(config.getGraphicsMode());
         this.fsm = new TelnetFSM(config, screenBuffer, dsProcessor);
         this.inputProcessor = new InputProcessor(screenBuffer, translator, fsm);
+        this.ps = new haus.nightmare.lib3270j.ecl.ECLPS(screenBuffer, inputProcessor, translator);
+        this.oia = new haus.nightmare.lib3270j.ecl.ECLOIA(screenBuffer, inputProcessor, fsm);
 
         // Wire up the output sender: DSProcessor -> FSM -> TelnetConnection
         dsProcessor.setOutputSender(fsm::send3270Data);
@@ -125,6 +129,18 @@ public class Telnet3270Client {
     /** Get the connection config. */
     public ConnectionConfig getConfig() { return config; }
 
+    /** Get the ECL Presentation Space API. */
+    public haus.nightmare.lib3270j.ecl.ECLPS getPS() { return ps; }
+
+    /** Get the ECL Operator Information Area API. */
+    public haus.nightmare.lib3270j.ecl.ECLOIA getOIA() { return oia; }
+
+    /** Get the list of all fields currently on screen. */
+    public haus.nightmare.lib3270j.ecl.ECLFieldList getFieldList() { return ps.getFieldList(); }
+
+    /** Send IBM ECL bracketed mnemonic keystrokes (e.g. "USER[tab]PASS[enter]"). */
+    public void sendKeys(String keys) { inputProcessor.sendKeys(keys); }
+
     /** Set a custom or interactive TLS certificate verifier callback. */
     public void setTlsCertificateVerifier(haus.nightmare.lib3270j.tls.TlsCertificateVerifier verifier) {
         config.setCertificateVerifier(verifier);

lib3270j/src/main/java/haus/nightmare/lib3270j/ecl/ECLConstants.java

@@ -0,0 +1,52 @@
+package haus.nightmare.lib3270j.ecl;
+
+/**
+ * Common constants for IBM Host On-Demand Emulator Class Library (ECL) emulation.
+ */
+public interface ECLConstants {
+
+    // Presentation space logical planes
+    int PLANE_TEXT     = 1; // Unicode/EBCDIC characters
+    int PLANE_COLOR    = 2; // Color attributes
+    int PLANE_HILITE   = 3; // Extended highlighting
+    int PLANE_EXTENDED = 4; // Extended character sets / outlining
+    int PLANE_FIELD    = 5; // Field attribute definition bytes
+    int PLANE_DBCS     = 6; // Double-byte character plane
+
+    // Color definitions (IBM 3279 standard 16-color palette)
+    char COLOR_NEUTRAL_BLACK = 0;
+    char COLOR_BLUE          = 1;
+    char COLOR_RED           = 2;
+    char COLOR_PINK          = 3;
+    char COLOR_GREEN         = 4;
+    char COLOR_TURQUOISE     = 5;
+    char COLOR_YELLOW        = 6;
+    char COLOR_NEUTRAL_WHITE = 7;
+    char COLOR_BLACK         = 8;
+    char COLOR_DEEP_BLUE     = 9;
+    char COLOR_ORANGE        = 10;
+    char COLOR_PURPLE        = 11;
+    char COLOR_PALE_GREEN    = 12;
+    char COLOR_PALE_TURQUOISE= 13;
+    char COLOR_GREY          = 14;
+    char COLOR_WHITE         = 15;
+
+    // Highlighting attributes
+    char HILITE_DEFAULT    = 0x00;
+    char HILITE_BLINK      = 0xF1;
+    char HILITE_REVERSE    = 0xF2;
+    char HILITE_UNDERSCORE = 0xF4;
+
+    // Search directions
+    int SEARCH_FORWARD  = 1;
+    int SEARCH_BACKWARD = 2;
+
+    // OIA Input Inhibited Reason Codes
+    int INHIBIT_NOT_INHIBITED   = 0;
+    int INHIBIT_SYSTEM_LOCK     = 1; // X SYSTEM (Waiting for host response)
+    int INHIBIT_NUMERIC_ONLY    = 2; // X NUMERIC (Non-numeric in numeric field)
+    int INHIBIT_PROTECTED_FIELD = 3; // X PROT (Attempted write into protected field)
+    int INHIBIT_OVERFLOW        = 4; // X > (Insert mode buffer overflow)
+    int INHIBIT_COMM_CHECK      = 5; // X COMM (Communication or socket check)
+    int INHIBIT_OPERATOR_DUE    = 6; // X OP (Operator Intervention Due)
+}

lib3270j/src/main/java/haus/nightmare/lib3270j/ecl/ECLField.java

@@ -0,0 +1,148 @@
+package haus.nightmare.lib3270j.ecl;
+
+import static haus.nightmare.lib3270j.protocol.DS3270Constants.*;
+
+/**
+ * Represents a discrete 3270 field within an IBM Host On-Demand Presentation Space.
+ * Provides programmatic inspection and modification of field text and attributes.
+ */
+public class ECLField {
+
+    private final ECLPS ps;
+    private final int startPos;   // Position of field attribute byte
+    private final int dataStart;  // First data position (startPos + 1 wrapped)
+    private final int endPos;     // Last data position inclusive
+    private final int length;     // Usable data character length
+    private final byte attribute; // Field attribute byte (FA)
+
+    public ECLField(ECLPS ps, int startPos, int dataStart, int endPos, int length, byte attribute) {
+        this.ps = ps;
+        this.startPos = startPos;
+        this.dataStart = dataStart;
+        this.endPos = endPos;
+        this.length = length;
+        this.attribute = attribute;
+    }
+
+    /** Buffer address of the field attribute character. */
+    public int getStart() { return startPos; }
+
+    /** First buffer address of the field data (start + 1). */
+    public int getDataStart() { return dataStart; }
+
+    /** Last buffer address of the field data inclusive. */
+    public int getEnd() { return endPos; }
+
+    /** Number of data characters in the field. */
+    public int getLength() { return length; }
+
+    public int getStartRow() {
+        int cols = ps.getCols();
+        return cols > 0 ? startPos / cols : 0;
+    }
+
+    public int getStartCol() {
+        int cols = ps.getCols();
+        return cols > 0 ? startPos % cols : 0;
+    }
+
+    public int getEndRow() {
+        int cols = ps.getCols();
+        return cols > 0 ? endPos / cols : 0;
+    }
+
+    public int getEndCol() {
+        int cols = ps.getCols();
+        return cols > 0 ? endPos % cols : 0;
+    }
+
+    public boolean isModified() {
+        return faIsModified(attribute & 0xFF);
+    }
+
+    public boolean isProtected() {
+        return faIsProtected(attribute & 0xFF);
+    }
+
+    public boolean isNumeric() {
+        return faIsNumeric(attribute & 0xFF);
+    }
+
+    public boolean isHighIntensity() {
+        return faIsHigh(attribute & 0xFF);
+    }
+
+    public boolean isHidden() {
+        return faIsZero(attribute & 0xFF);
+    }
+
+    public boolean isDisplay() {
+        return !isHidden();
+    }
+
+    public boolean isPenSelectable() {
+        return faIsSelectable(attribute & 0xFF);
+    }
+
+    public short getAttribute() {
+        return (short) (attribute & 0xFF);
+    }
+
+    /**
+     * Get the text contents of this field as a String.
+     */
+    public String getText() {
+        if (length <= 0) return "";
+        return ps.getString(dataStart, length);
+    }
+
+    /**
+     * Set the text contents of this field.
+     */
+    public void setText(String text) {
+        if (isProtected() || length <= 0) return;
+        ps.setText(text, dataStart);
+    }
+
+    /**
+     * Get selector light pen type.
+     * Returns '?' for selectable, '>' for selected, ' ' for space/unselectable.
+     */
+    public char getSelectorPenType() {
+        if (length <= 0) return ' ';
+        String t = getText();
+        if (!t.isEmpty()) {
+            char first = t.charAt(0);
+            if (first == '?' || first == '>') return first;
+        }
+        return ' ';
+    }
+
+    /**
+     * Actuate lightpen selection on this field ('?' -> '>').
+     */
+    public void selectField() {
+        if (isProtected() || length <= 0) return;
+        String t = getText();
+        if (!t.isEmpty() && t.charAt(0) == '?') {
+            setText(">" + (t.length() > 1 ? t.substring(1) : ""));
+        }
+    }
+
+    /**
+     * Deselect lightpen selection on this field ('>' -> '?').
+     */
+    public void deSelectField() {
+        if (isProtected() || length <= 0) return;
+        String t = getText();
+        if (!t.isEmpty() && t.charAt(0) == '>') {
+            setText("?" + (t.length() > 1 ? t.substring(1) : ""));
+        }
+    }
+
+    @Override
+    public String toString() {
+        return String.format("ECLField[start=%d, end=%d, len=%d, prot=%b, mod=%b, text=\"%s\"]",
+            startPos, endPos, length, isProtected(), isModified(), getText());
+    }
+}

lib3270j/src/main/java/haus/nightmare/lib3270j/ecl/ECLFieldList.java

@@ -0,0 +1,152 @@
+package haus.nightmare.lib3270j.ecl;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import haus.nightmare.lib3270j.screen.ScreenBuffer;
+import haus.nightmare.lib3270j.screen.ExtendedAttribute;
+
+/**
+ * Manages the collection of all 3270 fields currently present in the Presentation Space.
+ * Conforms to IBM ECL ECLFieldList specification.
+ */
+public class ECLFieldList {
+
+    private final ECLPS ps;
+    private final ScreenBuffer screen;
+    private final List<ECLField> fields = new ArrayList<>();
+
+    public ECLFieldList(ECLPS ps, ScreenBuffer screen) {
+        this.ps = ps;
+        this.screen = screen;
+        refresh();
+    }
+
+    /**
+     * Refresh the field list by scanning the presentation space buffer.
+     */
+    public synchronized void refresh() {
+        fields.clear();
+        if (screen == null || !screen.isFormatted()) {
+            return;
+        }
+
+        int rows = screen.getRows();
+        int cols = screen.getCols();
+        int size = rows * cols;
+        if (size <= 0) return;
+
+        // Collect all field attribute positions
+        List<Integer> faPositions = new ArrayList<>();
+        for (int i = 0; i < size; i++) {
+            ExtendedAttribute ea = screen.getCell(i);
+            if (ea.isFieldAttribute()) {
+                faPositions.add(i);
+            }
+        }
+
+        if (faPositions.isEmpty()) {
+            return;
+        }
+
+        int numFields = faPositions.size();
+        for (int i = 0; i < numFields; i++) {
+            int startPos = faPositions.get(i);
+            int nextFaPos = faPositions.get((i + 1) % numFields);
+
+            int dataStart = (startPos + 1) % size;
+            int endPos = (nextFaPos == 0) ? size - 1 : nextFaPos - 1;
+
+            int len;
+            if (nextFaPos > startPos) {
+                len = nextFaPos - startPos - 1;
+            } else {
+                len = (size - startPos - 1) + nextFaPos;
+            }
+
+            byte faVal = screen.getCell(startPos).fa;
+            fields.add(new ECLField(ps, startPos, dataStart, endPos, len, faVal));
+        }
+    }
+
+    public synchronized int getFieldCount() {
+        return fields.size();
+    }
+
+    public synchronized List<ECLField> getFields() {
+        return Collections.unmodifiableList(new ArrayList<>(fields));
+    }
+
+    public synchronized ECLField getFirstField() {
+        if (fields.isEmpty()) return null;
+        return fields.get(0);
+    }
+
+    public synchronized ECLField getNextField(ECLField prev) {
+        if (prev == null || fields.isEmpty()) return getFirstField();
+        int idx = fields.indexOf(prev);
+        if (idx >= 0 && idx + 1 < fields.size()) {
+            return fields.get(idx + 1);
+        }
+        return null;
+    }
+
+    /**
+     * Find the field that contains the specified buffer position.
+     */
+    public synchronized ECLField findField(int pos) {
+        if (fields.isEmpty() || screen == null) return null;
+        int size = screen.getRows() * screen.getCols();
+        if (size <= 0) return null;
+        pos = ((pos % size) + size) % size;
+
+        for (ECLField f : fields) {
+            int start = f.getStart();
+            int end = f.getEnd();
+            if (start <= end) {
+                if (pos >= start && pos <= end) return f;
+            } else {
+                // Wrapped field
+                if (pos >= start || pos <= end) return f;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Find the field at the specified 0-indexed row and column.
+     */
+    public ECLField findField(int row, int col) {
+        if (screen == null) return null;
+        int cols = screen.getCols();
+        return findField(row * cols + col);
+    }
+
+    /**
+     * Find field containing the given text string.
+     */
+    public synchronized ECLField findField(String text, int startPos) {
+        if (text == null || text.isEmpty() || fields.isEmpty()) return null;
+        int size = screen.getRows() * screen.getCols();
+        if (size <= 0) return null;
+        startPos = ((startPos % size) + size) % size;
+
+        // Find starting index in field list
+        int startIdx = 0;
+        for (int i = 0; i < fields.size(); i++) {
+            if (fields.get(i).getStart() >= startPos) {
+                startIdx = i;
+                break;
+            }
+        }
+
+        for (int i = startIdx; i < fields.size(); i++) {
+            ECLField f = fields.get(i);
+            if (f.getText().contains(text)) {
+                return f;
+            }
+        }
+        return null;
+    }
+}

lib3270j/src/main/java/haus/nightmare/lib3270j/ecl/ECLOIA.java

@@ -0,0 +1,143 @@
+package haus.nightmare.lib3270j.ecl;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import haus.nightmare.lib3270j.input.InputProcessor;
+import haus.nightmare.lib3270j.screen.ScreenBuffer;
+import haus.nightmare.lib3270j.telnet.TelnetFSM;
+import static haus.nightmare.lib3270j.protocol.DS3270Constants.*;
+
+/**
+ * Operator Information Area (OIA) status engine matching IBM Host On-Demand ECL specification.
+ * Provides synchronization primitives (waitForInput, waitForSysAvailable) and status inspection.
+ */
+public class ECLOIA implements ECLConstants {
+
+    private final ScreenBuffer screen;
+    private final InputProcessor inputProcessor;
+    private final TelnetFSM fsm;
+    private final List<ECLOIANotify> listeners = new ArrayList<>();
+
+    public interface ECLOIANotify {
+        void onOIAChanged(ECLOIA oia);
+    }
+
+    public ECLOIA(ScreenBuffer screen, InputProcessor inputProcessor, TelnetFSM fsm) {
+        this.screen = screen;
+        this.inputProcessor = inputProcessor;
+        this.fsm = fsm;
+
+        if (inputProcessor != null) {
+            inputProcessor.setLockStateListener(locked -> notifyOIAChanged());
+        }
+    }
+
+    public synchronized void registerOIAEvent(ECLOIANotify listener) {
+        if (listener != null && !listeners.contains(listener)) {
+            listeners.add(listener);
+        }
+    }
+
+    public synchronized void unregisterOIAEvent(ECLOIANotify listener) {
+        listeners.remove(listener);
+    }
+
+    private synchronized void notifyOIAChanged() {
+        for (ECLOIANotify l : listeners) {
+            try {
+                l.onOIAChanged(this);
+            } catch (Exception ignored) {}
+        }
+    }
+
+    public boolean isInsertMode() {
+        return inputProcessor != null && inputProcessor.isInsertMode();
+    }
+
+    public boolean isNumeric() {
+        if (screen == null || !screen.isFormatted()) return false;
+        byte fa = screen.getFieldAttributeAt(screen.getCursorAddress());
+        return faIsNumeric(fa & 0xFF);
+    }
+
+    public boolean isAlphanumeric() {
+        return !isNumeric();
+    }
+
+    public boolean isMessageWaiting() {
+        return false;
+    }
+
+    public boolean isCommError() {
+        return fsm != null && fsm.getConnectionState() != null && !fsm.getConnectionState().isConnected();
+    }
+
+    /**
+     * Get the current Input Inhibited code.
+     * Returns one of INHIBIT_* constants from ECLConstants.
+     */
+    public int getInputInhibited() {
+        if (isCommError()) {
+            return INHIBIT_COMM_CHECK;
+        }
+        if (inputProcessor != null && inputProcessor.isKeyboardLocked()) {
+            return INHIBIT_SYSTEM_LOCK;
+        }
+        return INHIBIT_NOT_INHIBITED;
+    }
+
+    /**
+     * Block until the keyboard becomes unlocked and ready for user input, or timeout expires.
+     * @return true if keyboard unlocked, false if timeout occurred.
+     */
+    public boolean waitForInput(long timeoutMs) {
+        long start = System.currentTimeMillis();
+        while (System.currentTimeMillis() - start < timeoutMs) {
+            if (getInputInhibited() == INHIBIT_NOT_INHIBITED) {
+                return true;
+            }
+            try {
+                Thread.sleep(20);
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+                return false;
+            }
+        }
+        return getInputInhibited() == INHIBIT_NOT_INHIBITED;
+    }
+
+    /**
+     * Block until the host system is available.
+     */
+    public boolean waitForSysAvailable(long timeoutMs) {
+        return waitForInput(timeoutMs);
+    }
+
+    /**
+     * Block until application is available.
+     */
+    public boolean waitForAppAvailable(long timeoutMs) {
+        return waitForInput(timeoutMs);
+    }
+
+    /**
+     * Block until any OIA transition occurs.
+     */
+    public boolean waitForTransition(long timeoutMs) {
+        int initialInhibit = getInputInhibited();
+        long start = System.currentTimeMillis();
+        while (System.currentTimeMillis() - start < timeoutMs) {
+            if (getInputInhibited() != initialInhibit) {
+                return true;
+            }
+            try {
+                Thread.sleep(20);
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+                return false;
+            }
+        }
+        return getInputInhibited() != initialInhibit;
+    }
+}

lib3270j/src/main/java/haus/nightmare/lib3270j/ecl/ECLPS.java

@@ -0,0 +1,237 @@
+package haus.nightmare.lib3270j.ecl;
+
+import haus.nightmare.lib3270j.charset.EbcdicTranslator;
+import haus.nightmare.lib3270j.input.InputProcessor;
+import haus.nightmare.lib3270j.screen.ExtendedAttribute;
+import haus.nightmare.lib3270j.screen.ScreenBuffer;
+import static haus.nightmare.lib3270j.protocol.DS3270Constants.*;
+
+/**
+ * Presentation Space (ECLPS) implementation conforming to IBM Host On-Demand ECL specification.
+ * Provides multi-plane presentation buffer access, string searches, formatted field navigation,
+ * and automated keystroke streaming.
+ */
+public class ECLPS implements ECLConstants {
+
+    private final ScreenBuffer screen;
+    private final InputProcessor inputProcessor;
+    private final EbcdicTranslator translator;
+    private final ECLFieldList fieldList;
+
+    public ECLPS(ScreenBuffer screen, InputProcessor inputProcessor, EbcdicTranslator translator) {
+        this.screen = screen;
+        this.inputProcessor = inputProcessor;
+        this.translator = translator;
+        this.fieldList = new ECLFieldList(this, screen);
+    }
+
+    public ScreenBuffer getScreenBuffer() { return screen; }
+    public InputProcessor getInputProcessor() { return inputProcessor; }
+    public EbcdicTranslator getTranslator() { return translator; }
+    public ECLFieldList getFieldList() {
+        fieldList.refresh();
+        return fieldList;
+    }
+
+    public int getSize()     { return screen.getRows() * screen.getCols(); }
+    public int getRows()     { return screen.getRows(); }
+    public int getCols()     { return screen.getCols(); }
+    public int getCursorPos(){ return screen.getCursorAddress(); }
+    public int getCursorRow(){ return screen.getCursorRow(); }
+    public int getCursorCol(){ return screen.getCursorCol(); }
+
+    public void setCursorPos(int pos) {
+        screen.setCursorAddress(pos);
+    }
+
+    public void setCursorPos(int row, int col) {
+        int pos = screen.rowColToAddress(row, col);
+        screen.setCursorAddress(pos);
+    }
+
+    /**
+     * Copy presentation data from a specific plane into a destination buffer.
+     */
+    public synchronized int getPlane(int planeType, char[] destBuffer, int start, int length) {
+        if (destBuffer == null || screen == null || length <= 0) return 0;
+        int size = screen.getRows() * screen.getCols();
+        if (size <= 0) return 0;
+
+        start = ((start % size) + size) % size;
+        int copyLen = Math.min(length, destBuffer.length);
+
+        for (int i = 0; i < copyLen; i++) {
+            int addr = (start + i) % size;
+            ExtendedAttribute ea = screen.getCell(addr);
+            switch (planeType) {
+                case PLANE_TEXT:
+                    if (ea.isFieldAttribute()) {
+                        destBuffer[i] = ' ';
+                    } else if (ea.ucs4 != 0) {
+                        destBuffer[i] = (char) ea.ucs4;
+                    } else if (ea.ec != 0) {
+                        destBuffer[i] = translator.ebcdicToUnicode(ea.ec & 0xFF);
+                    } else {
+                        destBuffer[i] = ' ';
+                    }
+                    break;
+                case PLANE_COLOR:
+                    destBuffer[i] = (char) (ea.fg & 0xFF);
+                    break;
+                case PLANE_HILITE:
+                    destBuffer[i] = (char) (ea.gr & 0xFF);
+                    break;
+                case PLANE_EXTENDED:
+                    destBuffer[i] = (char) (ea.cs & 0xFF);
+                    break;
+                case PLANE_FIELD:
+                    destBuffer[i] = ea.isFieldAttribute() ? (char) (ea.fa & 0xFF) : 0;
+                    break;
+                default:
+                    destBuffer[i] = ' ';
+                    break;
+            }
+        }
+        return copyLen;
+    }
+
+    /**
+     * Get a string of characters from the presentation space starting at address pos.
+     */
+    public synchronized String getString(int pos, int length) {
+        if (length <= 0) return "";
+        char[] buf = new char[length];
+        getPlane(PLANE_TEXT, buf, pos, length);
+        return new String(buf);
+    }
+
+    /**
+     * Get a string of characters from the presentation space starting at row/column.
+     */
+    public String getString(int row, int col, int length) {
+        int pos = screen.rowColToAddress(row, col);
+        return getString(pos, length);
+    }
+
+    /**
+     * Insert text directly into unprotected fields in the presentation space starting at pos.
+     */
+    public synchronized void setText(String text, int pos) {
+        if (text == null || text.isEmpty() || screen == null) return;
+        int size = screen.getRows() * screen.getCols();
+        if (size <= 0) return;
+
+        pos = ((pos % size) + size) % size;
+        setCursorPos(pos);
+
+        for (int i = 0; i < text.length(); i++) {
+            char ch = text.charAt(i);
+            inputProcessor.typeCharacter(ch);
+        }
+    }
+
+    /**
+     * Insert text starting at row and column.
+     */
+    public void setText(String text, int row, int col) {
+        int pos = screen.rowColToAddress(row, col);
+        setText(text, pos);
+    }
+
+    /**
+     * Search for a string in the presentation space.
+     * Returns 1-based or 0-based position, or -1 if not found.
+     */
+    public synchronized int searchString(String target, int startRow, int startCol, int dir, boolean ignoreCase) {
+        if (target == null || target.isEmpty() || screen == null) return -1;
+        int rows = screen.getRows();
+        int cols = screen.getCols();
+        int size = rows * cols;
+        if (size <= 0) return -1;
+
+        int startPos = (startRow * cols + startCol) % size;
+        char[] fullScreen = new char[size];
+        getPlane(PLANE_TEXT, fullScreen, 0, size);
+        String screenText = new String(fullScreen);
+
+        if (ignoreCase) {
+            screenText = screenText.toLowerCase();
+            target = target.toLowerCase();
+        }
+
+        int targetLen = target.length();
+        if (dir == SEARCH_FORWARD) {
+            // Forward search with wrapping
+            for (int i = 0; i < size; i++) {
+                int pos = (startPos + i) % size;
+                if (matchesAt(screenText, target, pos, size)) {
+                    return pos;
+                }
+            }
+        } else {
+            // Backward search with wrapping
+            for (int i = 0; i < size; i++) {
+                int pos = (startPos - i + size) % size;
+                if (matchesAt(screenText, target, pos, size)) {
+                    return pos;
+                }
+            }
+        }
+        return -1;
+    }
+
+    private boolean matchesAt(String screenText, String target, int pos, int size) {
+        int len = target.length();
+        for (int j = 0; j < len; j++) {
+            int charPos = (pos + j) % size;
+            if (screenText.charAt(charPos) != target.charAt(j)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Paste text with line wrapping across unprotected fields.
+     */
+    public synchronized int pasteLineWrap(String text, int startPos, int endCol, boolean wordWrap) {
+        if (text == null || text.isEmpty() || screen == null) return 0;
+        int cols = screen.getCols();
+        int rows = screen.getRows();
+        int size = rows * cols;
+        if (size <= 0) return 0;
+
+        setCursorPos(startPos);
+        int charsPasted = 0;
+        String[] lines = text.split("\r?\n");
+
+        for (int l = 0; l < lines.length; l++) {
+            String line = lines[l];
+            for (int i = 0; i < line.length(); i++) {
+                int curPos = screen.getCursorAddress();
+                int curCol = curPos % cols;
+                if (endCol > 0 && curCol >= endCol) {
+                    // Advance to next row
+                    int nextRow = (curPos / cols + 1) % rows;
+                    setCursorPos(nextRow * cols);
+                }
+                inputProcessor.typeCharacter(line.charAt(i));
+                charsPasted++;
+            }
+            if (l < lines.length - 1) {
+                // Newline key between lines
+                inputProcessor.newline();
+            }
+        }
+        return charsPasted;
+    }
+
+    /**
+     * Send standard IBM ECL mnemonic keystrokes.
+     */
+    public void sendKeys(String keys) {
+        if (inputProcessor != null) {
+            inputProcessor.sendKeys(keys);
+        }
+    }
+}

lib3270j/src/main/java/haus/nightmare/lib3270j/input/InputProcessor.java

@@ -863,6 +863,204 @@ public class InputProcessor {
         return fieldLen;
     }
 
+    /**
+     * Parse and execute IBM ECL standard mnemonic keystrokes (e.g. "USER[tab]PASS[enter]").
+     */
+    public void sendKeys(String keys) {
+        if (keys == null || keys.isEmpty()) return;
+
+        int len = keys.length();
+        int i = 0;
+        while (i < len) {
+            char c = keys.charAt(i);
+            if (c == '[') {
+                int end = keys.indexOf(']', i);
+                if (end > i) {
+                    String token = keys.substring(i + 1, end).trim().toLowerCase();
+                    executeMnemonicToken(token);
+                    i = end + 1;
+                    continue;
+                }
+            }
+            typeCharacter(c);
+            i++;
+        }
+    }
+
+    private void executeMnemonicToken(String token) {
+        switch (token) {
+            case "enter":
+            case "return":
+                sendAid(AID_ENTER);
+                break;
+            case "clear":
+                sendAid(AID_CLEAR);
+                break;
+            case "tab":
+                tab();
+                break;
+            case "backtab":
+            case "btab":
+                backTab();
+                break;
+            case "newline":
+            case "nl":
+                newline();
+                break;
+            case "home":
+                cursorHome();
+                break;
+            case "up":
+            case "curup":
+                cursorUp();
+                break;
+            case "down":
+            case "curdown":
+                cursorDown();
+                break;
+            case "left":
+            case "curleft":
+                cursorLeft();
+                break;
+            case "right":
+            case "curright":
+                cursorRight();
+                break;
+            case "eraseeof":
+            case "erase_eof":
+                eraseEof();
+                break;
+            case "eraseinp":
+            case "erase_input":
+                eraseInput();
+                break;
+            case "dup":
+                dup();
+                break;
+            case "fm":
+            case "fieldmark":
+                fieldMark();
+                break;
+            case "attn":
+                attn();
+                break;
+            case "sysreq":
+                sysReq();
+                break;
+            case "reset":
+                reset();
+                break;
+            case "insert":
+                setInsertMode(!isInsertMode());
+                break;
+            case "delete":
+                deleteChar();
+                break;
+            case "backspace":
+            case "bs":
+                backspace();
+                break;
+            case "wordtab":
+                processWordTab(true);
+                break;
+            case "wordbacktab":
+                processWordTab(false);
+                break;
+            case "deleteword":
+                processDeleteWord();
+                break;
+            default:
+                if (token.startsWith("pf")) {
+                    try {
+                        int pfNum = Integer.parseInt(token.substring(2));
+                        if (pfNum >= 1 && pfNum <= 24) {
+                            sendAid(AID_PF1 + (pfNum - 1));
+                        }
+                    } catch (NumberFormatException ignored) {}
+                } else if (token.startsWith("pa")) {
+                    try {
+                        int paNum = Integer.parseInt(token.substring(2));
+                        if (paNum >= 1 && paNum <= 3) {
+                            sendAid(AID_PA1 + (paNum - 1));
+                        }
+                    } catch (NumberFormatException ignored) {}
+                }
+                break;
+        }
+    }
+
+    /**
+     * Jump cursor to next or previous word boundary.
+     */
+    public void processWordTab(boolean forward) {
+        if (keyboardLocked || screen == null) return;
+        int size = screen.getRows() * screen.getCols();
+        if (size <= 0) return;
+
+        int cur = screen.getCursorAddress();
+        if (forward) {
+            // Find next whitespace then next non-whitespace
+            int pos = screen.incrementAddress(cur);
+            int count = 0;
+            while (count < size && !isWhitespaceOrNull(pos)) {
+                pos = screen.incrementAddress(pos);
+                count++;
+            }
+            while (count < size && isWhitespaceOrNull(pos)) {
+                pos = screen.incrementAddress(pos);
+                count++;
+            }
+            screen.setCursorAddress(pos);
+        } else {
+            // Find previous non-whitespace after whitespace
+            int pos = screen.decrementAddress(cur);
+            int count = 0;
+            while (count < size && isWhitespaceOrNull(pos)) {
+                pos = screen.decrementAddress(pos);
+                count++;
+            }
+            while (count < size && !isWhitespaceOrNull(screen.decrementAddress(pos))) {
+                pos = screen.decrementAddress(pos);
+                count++;
+            }
+            screen.setCursorAddress(pos);
+        }
+        screen.markAllChanged();
+        screen.updateDisplaySnapshot();
+    }
+
+    /**
+     * Delete the word starting at the cursor position.
+     */
+    public void processDeleteWord() {
+        if (keyboardLocked || screen == null) return;
+        int cur = screen.getCursorAddress();
+        if (screen.isFormatted()) {
+            byte fa = screen.getFieldAttributeAt(cur);
+            if (faIsProtected(fa & 0xFF)) return;
+        }
+
+        int count = 0;
+        int size = screen.getRows() * screen.getCols();
+        while (count < size && !isWhitespaceOrNull(screen.getCursorAddress())) {
+            deleteChar();
+            count++;
+        }
+        // Also delete trailing spaces
+        while (count < size && isWhitespaceOrNull(screen.getCursorAddress()) && screen.getCell(screen.getCursorAddress()).ec != 0) {
+            deleteChar();
+            count++;
+        }
+    }
+
+    private boolean isWhitespaceOrNull(int pos) {
+        if (screen == null) return true;
+        ExtendedAttribute ea = screen.getCell(pos);
+        if (ea.isFieldAttribute()) return true;
+        int ec = ea.ec & 0xFF;
+        return ec == 0 || ec == 0x40; // Null or EBCDIC Space
+    }
+
     /**
      * Send a structured field response directly.
      * Used by DFT mode file transfer.

lib3270j/src/test/java/haus/nightmare/lib3270j/ecl/ECLFieldListTest.java

@@ -0,0 +1,97 @@
+package haus.nightmare.lib3270j.ecl;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+import haus.nightmare.lib3270j.TerminalModel;
+import haus.nightmare.lib3270j.charset.EbcdicTranslator;
+import haus.nightmare.lib3270j.input.InputProcessor;
+import haus.nightmare.lib3270j.screen.ScreenBuffer;
+import static haus.nightmare.lib3270j.protocol.DS3270Constants.*;
+
+public class ECLFieldListTest {
+
+    private ScreenBuffer screen;
+    private EbcdicTranslator translator;
+    private InputProcessor input;
+    private ECLPS ps;
+
+    @BeforeEach
+    public void setup() {
+        translator = new EbcdicTranslator();
+        screen = new ScreenBuffer(TerminalModel.IBM_3278_2, translator);
+        input = new InputProcessor(screen, translator, null);
+        ps = new ECLPS(screen, input, translator);
+    }
+
+    @Test
+    public void testFieldListDetection() {
+        // Create 2 fields: pos 0 (unprotected, 9 chars), pos 10 (protected, 19 chars), pos 30 (high intensity)
+        screen.setFieldAttribute(0, (byte) FA_PRINTABLE);
+        screen.setFieldAttribute(10, (byte) (FA_PRINTABLE | FA_PROTECT));
+        screen.setFieldAttribute(30, (byte) (FA_PRINTABLE | FA_INT_HIGH_SEL));
+
+        ECLFieldList list = ps.getFieldList();
+        assertEquals(3, list.getFieldCount());
+
+        ECLField f1 = list.getFirstField();
+        assertNotNull(f1);
+        assertEquals(0, f1.getStart());
+        assertEquals(1, f1.getDataStart());
+        assertEquals(9, f1.getEnd());
+        assertEquals(9, f1.getLength());
+        assertFalse(f1.isProtected());
+
+        ECLField f2 = list.getNextField(f1);
+        assertNotNull(f2);
+        assertEquals(10, f2.getStart());
+        assertEquals(11, f2.getDataStart());
+        assertEquals(29, f2.getEnd());
+        assertEquals(19, f2.getLength());
+        assertTrue(f2.isProtected());
+
+        ECLField f3 = list.getNextField(f2);
+        assertNotNull(f3);
+        assertEquals(30, f3.getStart());
+        assertTrue(f3.isHighIntensity());
+        assertTrue(f3.isPenSelectable());
+
+        assertNull(list.getNextField(f3));
+    }
+
+    @Test
+    public void testFindFieldByPositionAndRowCol() {
+        screen.setFieldAttribute(0, (byte) FA_PRINTABLE);
+        screen.setFieldAttribute(80, (byte) (FA_PRINTABLE | FA_PROTECT));
+
+        ECLFieldList list = ps.getFieldList();
+        ECLField found1 = list.findField(40);
+        assertNotNull(found1);
+        assertEquals(0, found1.getStart());
+
+        ECLField found2 = list.findField(1, 10); // Row 1, Col 10 -> addr 90
+        assertNotNull(found2);
+        assertEquals(80, found2.getStart());
+        assertTrue(found2.isProtected());
+    }
+
+    @Test
+    public void testLightpenSelectionOnField() {
+        screen.setFieldAttribute(0, (byte) (FA_PRINTABLE | FA_INT_HIGH_SEL));
+        screen.setCell(1, translator.unicodeToEbcdic('?'));
+        screen.setCell(2, translator.unicodeToEbcdic('O'));
+        screen.setCell(3, translator.unicodeToEbcdic('K'));
+        screen.setFieldAttribute(10, (byte) (FA_PRINTABLE | FA_PROTECT));
+        screen.translateToUnicode();
+
+        ECLField field = ps.getFieldList().getFirstField();
+        assertEquals('?', field.getSelectorPenType());
+
+        field.selectField();
+        assertEquals('>', field.getSelectorPenType());
+
+        field.deSelectField();
+        assertEquals('?', field.getSelectorPenType());
+    }
+}

lib3270j/src/test/java/haus/nightmare/lib3270j/ecl/ECLOIATest.java

@@ -0,0 +1,59 @@
+package haus.nightmare.lib3270j.ecl;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import haus.nightmare.lib3270j.TerminalModel;
+import haus.nightmare.lib3270j.charset.EbcdicTranslator;
+import haus.nightmare.lib3270j.input.InputProcessor;
+import haus.nightmare.lib3270j.screen.ScreenBuffer;
+import static haus.nightmare.lib3270j.ecl.ECLConstants.*;
+
+public class ECLOIATest {
+
+    private ScreenBuffer screen;
+    private EbcdicTranslator translator;
+    private InputProcessor input;
+    private ECLOIA oia;
+
+    @BeforeEach
+    public void setup() {
+        translator = new EbcdicTranslator();
+        screen = new ScreenBuffer(TerminalModel.IBM_3278_2, translator);
+        input = new InputProcessor(screen, translator, null);
+        oia = new ECLOIA(screen, input, null);
+    }
+
+    @Test
+    public void testInhibitStateTransitions() {
+        assertEquals(INHIBIT_NOT_INHIBITED, oia.getInputInhibited());
+        assertTrue(oia.waitForInput(100));
+
+        input.setKeyboardLocked(true);
+        assertEquals(INHIBIT_SYSTEM_LOCK, oia.getInputInhibited());
+        assertFalse(oia.waitForInput(50));
+
+        input.setKeyboardLocked(false);
+        assertEquals(INHIBIT_NOT_INHIBITED, oia.getInputInhibited());
+        assertTrue(oia.waitForInput(100));
+    }
+
+    @Test
+    public void testOIAEventListener() {
+        AtomicBoolean triggered = new AtomicBoolean(false);
+        oia.registerOIAEvent(changedOia -> triggered.set(true));
+
+        input.setKeyboardLocked(true);
+        assertTrue(triggered.get());
+    }
+
+    @Test
+    public void testInsertModeState() {
+        assertFalse(oia.isInsertMode());
+        input.setInsertMode(true);
+        assertTrue(oia.isInsertMode());
+    }
+}

lib3270j/src/test/java/haus/nightmare/lib3270j/ecl/ECLPSTest.java

@@ -0,0 +1,117 @@
+package haus.nightmare.lib3270j.ecl;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+import haus.nightmare.lib3270j.TerminalModel;
+import haus.nightmare.lib3270j.charset.EbcdicTranslator;
+import haus.nightmare.lib3270j.input.InputProcessor;
+import haus.nightmare.lib3270j.screen.ScreenBuffer;
+import haus.nightmare.lib3270j.telnet.TelnetFSM;
+import static haus.nightmare.lib3270j.protocol.DS3270Constants.*;
+
+public class ECLPSTest implements ECLConstants {
+
+    private ScreenBuffer screen;
+    private EbcdicTranslator translator;
+    private InputProcessor input;
+    private ECLPS ps;
+
+    @BeforeEach
+    public void setup() {
+        translator = new EbcdicTranslator();
+        screen = new ScreenBuffer(TerminalModel.IBM_3278_2, translator);
+        input = new InputProcessor(screen, translator, null);
+        ps = new ECLPS(screen, input, translator);
+    }
+
+    @Test
+    public void testGeometry() {
+        assertEquals(24, ps.getRows());
+        assertEquals(80, ps.getCols());
+        assertEquals(24 * 80, ps.getSize());
+        assertEquals(0, ps.getCursorPos());
+
+        ps.setCursorPos(10, 20);
+        assertEquals(10 * 80 + 20, ps.getCursorPos());
+        assertEquals(10, ps.getCursorRow());
+        assertEquals(20, ps.getCursorCol());
+    }
+
+    @Test
+    public void testPlaneTextExtractionAndSearch() {
+        // Set some text in buffer
+        screen.setCell(0, 0xC8); // 'H'
+        screen.setCell(1, 0xC5); // 'E'
+        screen.setCell(2, 0xD3); // 'L'
+        screen.setCell(3, 0xD3); // 'L'
+        screen.setCell(4, 0xD6); // 'O'
+        screen.translateToUnicode();
+
+        assertEquals("HELLO", ps.getString(0, 5));
+
+        // Search string forward
+        int pos = ps.searchString("ELL", 0, 0, SEARCH_FORWARD, false);
+        assertEquals(1, pos);
+
+        // Search string case-insensitive
+        int posLower = ps.searchString("hello", 0, 0, SEARCH_FORWARD, true);
+        assertEquals(0, posLower);
+
+        // Search not found
+        int notFound = ps.searchString("WORLD", 0, 0, SEARCH_FORWARD, false);
+        assertEquals(-1, notFound);
+    }
+
+    @Test
+    public void testMultiPlaneReading() {
+        screen.setFieldAttribute(0, (byte) (FA_PRINTABLE | FA_PROTECT));
+        screen.setCell(1, 0xC1); // 'A'
+        screen.getCell(1).fg = COLOR_RED;
+        screen.getCell(1).gr = (byte) HILITE_BLINK;
+
+        char[] textPlane = new char[2];
+        char[] colorPlane = new char[2];
+        char[] hilitePlane = new char[2];
+        char[] fieldPlane = new char[2];
+
+        ps.getPlane(PLANE_TEXT, textPlane, 0, 2);
+        ps.getPlane(PLANE_COLOR, colorPlane, 0, 2);
+        ps.getPlane(PLANE_HILITE, hilitePlane, 0, 2);
+        ps.getPlane(PLANE_FIELD, fieldPlane, 0, 2);
+
+        assertEquals(' ', textPlane[0]); // FA is space in text plane
+        assertEquals('A', textPlane[1]);
+
+        assertEquals(0, colorPlane[0]);
+        assertEquals(COLOR_RED, colorPlane[1]);
+
+        assertEquals(0, hilitePlane[0]);
+        assertEquals((char) (HILITE_BLINK & 0xFF), hilitePlane[1]);
+
+        assertTrue((fieldPlane[0] & 0xFF) != 0);
+        assertEquals(0, fieldPlane[1]);
+    }
+
+    @Test
+    public void testSendKeysMnemonics() {
+        // Create an unprotected field at pos 0
+        screen.setFieldAttribute(0, (byte) FA_PRINTABLE);
+        screen.setCursorAddress(1);
+
+        ps.sendKeys("IBM[tab]");
+        assertEquals('I', screen.getCell(1).ucs4);
+        assertEquals('B', screen.getCell(2).ucs4);
+        assertEquals('M', screen.getCell(3).ucs4);
+    }
+
+    @Test
+    public void testPasteLineWrap() {
+        screen.setFieldAttribute(0, (byte) FA_PRINTABLE);
+        screen.setCursorAddress(1);
+
+        int count = ps.pasteLineWrap("ABC\nDEF", 1, 80, false);
+        assertEquals(6, count);
+    }
+}